802.11ac & WIFI-6 clients getting low bandwidth speeds on 9800 CL WLC

[Evanjrosado]

Hi Everyone,

I hope someone can assist me on this one. I migrated my home Cisco lightweight network from a physical 2504 WLC to a virtual 9800 CL WLC 17.2.1 with a 3802e running flexconnect and a catalyst 1920 ap centrally switched. I put together and attached a diagram in hopes to make what i'm doing easier to understand and to have my work double checked because i'm surely no wireless expert :). 

So the problem i'm having is that my clients are getting speeds no higher than 90Mbps. For example in my home I have a  windows 10 client with a WIFI-6 capable adapter showing 1.2Gbps in the adapter status reading(see attached) and another windows 10 client with an 802.11ac client showing 866.7Mbps in the adapter status reading. Every time I run an iperf between both clients on the same WLAN the reading show that the clients are not getting anything over 90Mbps. I'm confused why this is occurring. 

I have tried bonding channels at 40, 80, and 160 but this only improves throughput minimally. Also when i run a show client on the AP it shows the these clients are getting 802.11ax and 802.11ac speeds with multiple streams. 

Can anyone help me with some pointers? 

[Rasika Nayanajith]

"3802e running flexconnect and a catalyst 1920 ap centrally switched"

Why these two APs in different modes, I would put them both into FlexConnect mode and let SSID does local switching.

If you wired connect these two laptops & do the same iperf test what speeds are you getting? I expect it is around 1Gbps mark

In wireless you may not get the same speed, I would expect 400-500Mpbs max. Leave iperf server on wired connections and test it again using two wireless laptops

https://mrncciew.com/2014/08/08/how-fast-is-your-network-iperf/

To have some understanding how your AP power/channel & client RSSI/SNR pls share below outupt from your wlc

c9800#show ap dot11 5ghz summary

c9800#show wireless client mac-address <client_mac_addr> detail | in dBm|Rate

HTH

Rasika 

[Evanjrosado]

Hi Rasika,

thank you for answering so fast. 

Okay so I originally configured the 9800 WLC with ISE running services with posture, guest and it works well with redirect and everything. When I encountered the low throughput I was curious to see if the speeds would improve if i used flexconnect but thats not the case. I had rough times trying to move the same ISE services using flexconnect so I am just offering WPA2 enterprise on flexconnect to client just for testing. 

To answer your question regarding iperf speeds, i'm getting 800Mbps between wired clients. Also consider that my AP's are connected to a 2.5 multigig POE switch port. 

I did what you instructed me to do and ran an iperf test between my wired and wireless clients. I'm seeing speeds around 120Mbps between wireless and wired client.

Here is a show client from the vwlc

vwlc01#show ap dot11 5ghz summary
AP Name Mac Address Slot Admin State Oper State Width Txpwr Channel Mode
---------------------------------------------------------------------------------------------------------------------------------------------------------
AP1920 7c21.0d44.7280 1 Enabled Up 80 5/8 (10 dBm) (40,36,44,48) Local

Here is a show client from the AP1920

AP1920#show client
access-lists Access-List Details
authentication Local authentication process information
opendns OpenDNS Info
statistics Client Statistics
summary Client Summary
AP1920#show client summary

Radio Driver client Summary:
==============================
apr0v0
-------
apr1v0
-------
authe_sta_list F0:6E:0B:C3:51:FD
authe_sta_list F4:8C:50:CA:B1:15
authe_sta_list F8:E4:E3:CB:BE:7A

WCP client Summary:
=====================

mac radio vap aid state encr Maxrate Assoc Cap is_wgb_wired wgb_mac_addr
F0:6E:0B:C3:51:FD 1 0 3 FWD AES_CCM128 MCS92SS VHT VHT false 00:00:00:00:00:00
F4:8C:50:CA:B1:15 1 0 2 FWD AES_CCM128 MCS92SS VHT VHT false 00:00:00:00:00:00
F8:E4:E3:CB:BE:7A 1 0 1 FWD AES_CCM128 MCS112SS HE HE false 00:00:00:00:00:00

Datapath IPv4 client Summary:
===============================
id vap port node tunnel mac seen_ip hashed_ip sniff_ago confirm_ago
F0:6E:0B:C3:51:FD 0 apr1v0 6.189.23.28 - F0:6E:0B:C3:51:FD 172.16.201.125 10.109.111.103 2.347000 2.346000
F4:8C:50:CA:B1:15 0 apr1v0 6.189.23.28 - F4:8C:50:CA:B1:15 172.16.201.113 10.163.135.206 3.931000 3.930000
F8:E4:E3:CB:BE:7A 0 apr1v0 6.189.23.28 - F8:E4:E3:CB:BE:7A 172.16.201.102 10.220.210.189 0.007000 0.006000

Datapath IPv6 client Summary:
===============================
client mac seen_ip6 age scope port
1 F0:6E:0B:C3:51:FD fe80::3cbe:df23:730a:ba22 85 link-local apr1v0
2 F4:8C:50:CA:B1:15 fe80::fd90:3cd8:9175:694f 131 link-local apr1v0
3 F8:E4:E3:CB:BE:7A fe80::f5bb:6054:31e9:372c 30 link-local apr1v0

[Evanjrosado]

Here are some iperf screenshots.

wireless to wired: at best 143Mbps

wireless to wireless: at best 70Mbps

[JPavonM]

Which wireless NIC do your laptops have? Which driver release?

If they are Intel based, take into consideration that Intel has improved performance in some of the latest versions of the driver for both, Wi-Fi 6 and Wi-Fi 5 wNIC's connected to Wi-Fi 6 AP's. Intel always recommend using manufacturer's drivers but I use to use the ones from them without any problem.

Additionally, have you reviewed your design to reduce CCI? How much contention is there on primary channel 40?

The values you are seeing in the wireless clients are not so far from the one that are expected if your AP is using only 20MHz channel due to CCI. See this excellent data rate cheat sheet including dot11ax capable clients here (https://www.semfionetworks.com/blog/mcs-table-updated-with-80211ax-data-rates).

HTH
-Jesus
*** Please Rate Helpful Responses ***

[Rasika Nayanajith · Accepted solution]

Thanks for the detail. If possible I would like to put your AP into clean 80MHz channel (ex ch 100-112 or 149-161 depend on what other APs consume your 5GHz spectrum)

I can see your AP still in local mode and traffic is not terminated on the switch (it may go to vWLC inside VM), just to isolate slowness is not due to centralized SSID, I would first make it local switching. Below guide may help you

https://www.cisco.com/c/en/us/support/docs/wireless/catalyst-9800-series-wireless-controllers/213945-understand-flexconnect-on-9800-wireless.html 

You should able to see mode REAP.

c9800#show ap dot11 5ghz summary
AP Name Mac Address Slot Admin State Oper State Width Txpwr Channel Mode
------------------------------------------------------------------------------------------------
C3702-AP02 b838.6184.c630 1 Enabled Up 80 2/8 (20 dBm) (149,153,157,161) REAP

In the previous output, I did not see client RSSI details. You can issue "show wireless client summary" CLI command first and get client MAC address. 

c9800#show wireless client summary
Number of Clients: 1

MAC Address AP Name Type ID State Protocol Method Role
------------------------------------------------------------------------------------------------
3a2f.30cc.f9a4 C3702-AP02 WLAN 20 Run 11ac None Local

Then issue "show wireless client mac-address " CLI command as shown below

c9800#show wireless client mac-address 3a2f.30cc.f9a4 detail | in dBm|Rate
Current Rate : m9 ss2

Supported Rates : 9.0,18.0,36.0,48.0,54.0
Radio Signal Strength Indicator : -37 dBm

In my case you can see, the client is connected m9, ss2 (ie MCS9 with 2 spatial streams). So your client is the limiting factor (even 9120AP is 4x4:4SS). Refer below the page to translate those rates into Mbps value

http://mcsindex.com/ 

These values are just data rate (not throughput), in wireless, you will have lot of management, control frames that consume airtime. So best case scenario, leave one wireless client on your AP and leave your iperf server wired connected. In that way you can test best throughput you get once your 11ac windows client connected and other time 11ax windows client connected.

HTH

Rasika

*** Pls rate all useful responses ***

[Evanjrosado]

Thanks for your reply. I agree with you and will try this configuration when I have a chance today.

I've attached preliminary testing WLAN client testing information showing WLAN NIC information, current throughput speed reading, and another Iperf test conducted this morning. I'm just going to focus on my 802.11ac capable clients for now. 

I hope this  information is helpful and I will configure the AP for flexconnect and provide an update. 

[Evanjrosado]

I did as instructed and did see improvement. I just expected more bandwidth out of WIFI6 enabled client. My AP is connected to a multigig port
and I can see that it negotiated and is using 2.5gig. Am I doing something wrong here? I appreciate all the input and am willing to try any suggestions.

Macintosh client 8c85.90cb.2a69 iperf results
Wireless to wired 200Mbps
Wireless to wireless 120Mbps

Windows 10 desktop f8e4.e3cb.be7a iperf results
Wireless to wired 205Mbps
Wireless to wireless 130Mbps

Windows 10 laptop f48c.50ca.b115 iperf results
Wireless to wired 190Mbps
Wireless to wireless 90Mbps

vwlc01#show ap dot11 5ghz summary
AP Name Mac Address Slot Admin State Oper State Width Txpwr Channel Mode
---------------------------------------------------------------------------------------------------------------------------------------------------------
AP1920 7c21.0d44.7280 1 Enabled Up 80 *1/8 (18 dBm) (100,104,108,112) REAP

vwlc01#show ap client sum
vwlc01#show wireless client summary
Number of Clients: 9

MAC Address AP Name Type ID State Protocol Method Role
-------------------------------------------------------------------------------------------------------------------------
8c85.90cb.2a69 AP1920 WLAN 4 Run 11ac None Local
f48c.50ca.b115 AP1920 WLAN 4 Run 11ac None Local
f8e4.e3cb.be7a AP1920 WLAN 4 Run 11ax(5) None Local

[Rasika Nayanajith]

That is a good sign.

I would suggest you test with one wireless client (go with ax client with mac-address f8e4.e3cb.be7a) connect to AP (no other wireless clients on the AP) to see the best-case scenario.

Pls post below output once you have that single client on the cell and doing your iperf test.

show wireless client mac-address f8e4.e3cb.be7a detail | in dBm|Rate

HTH

Rasika

*** Pls rate all useful responses ***

[Evanjrosado]

Thank you for the feedback. I will try this and report back the results as soon as I can. 

Do you have any experiences with running ISE services such as posture, guest services(hotspot, sponsored, self registered), etc with wireless using Flexconnect mode? Are there any limitations to running these services in Flexconnect mode?

I'm running many ISE services with much success on wireless using local mode/central switching but ran into issues when configuring these same services in Flexconnect mode so I gave up :(. I can definitely research documentation on my own but was just curious about your experiences. 

[Rasika Nayanajith]

I am not having a great deal of experience with ISE when it comes to those advanced features. If you have specific query below is the right place to post that query

https://community.cisco.com/t5/network-access-control/bd-p/discussions-network-access-control 

HTH

Rasika

[Evanjrosado]

Here are the results with only 1 wireless client connected and an iperf test to a wired client.

vwlc01#show wireless client mac-address f8e4.e3cb.be7a detail | in dBm|Rate
Current Rate : 13.5
Supported Rates : 6.0,18.0,36.0,48.0,54.0
Radio Signal Strength Indicator : -40 dBm

bin/iperf.exe -c 172.16.101.100 -P 1 -i 1 -p 5001 -C -f m -t 50
------------------------------------------------------------
Client connecting to 172.16.101.100, TCP port 5001
TCP window size: 0.06 MByte (default)
------------------------------------------------------------
[ 3] local 172.16.217.60 port 51936 connected with 172.16.101.100 port 5001
[ ID] Interval Transfer Bandwidth
[ 3] 0.0- 1.0 sec 23.8 MBytes 199 Mbits/sec
[ 3] 1.0- 2.0 sec 24.0 MBytes 201 Mbits/sec
[ 3] 2.0- 3.0 sec 23.1 MBytes 194 Mbits/sec
[ 3] 3.0- 4.0 sec 24.2 MBytes 203 Mbits/sec
[ 3] 4.0- 5.0 sec 23.9 MBytes 200 Mbits/sec
[ 3] 5.0- 6.0 sec 23.4 MBytes 196 Mbits/sec
[ 3] 6.0- 7.0 sec 23.8 MBytes 199 Mbits/sec
[ 3] 7.0- 8.0 sec 24.0 MBytes 201 Mbits/sec
[ 3] 8.0- 9.0 sec 23.1 MBytes 194 Mbits/sec
[ 3] 9.0-10.0 sec 23.5 MBytes 197 Mbits/sec
[ 3] 10.0-11.0 sec 23.5 MBytes 197 Mbits/sec
[ 3] 11.0-12.0 sec 23.6 MBytes 198 Mbits/sec
[ 3] 12.0-13.0 sec 24.1 MBytes 202 Mbits/sec
[ 3] 13.0-14.0 sec 23.9 MBytes 200 Mbits/sec
[ 3] 14.0-15.0 sec 23.9 MBytes 200 Mbits/sec
[ 3] 15.0-16.0 sec 23.4 MBytes 196 Mbits/sec
[ 3] 16.0-17.0 sec 22.8 MBytes 191 Mbits/sec
[ 3] 17.0-18.0 sec 23.6 MBytes 198 Mbits/sec
[ 3] 18.0-19.0 sec 23.6 MBytes 198 Mbits/sec
[ 3] 19.0-20.0 sec 23.5 MBytes 197 Mbits/sec
[ 3] 20.0-21.0 sec 23.8 MBytes 199 Mbits/sec
[ 3] 21.0-22.0 sec 23.8 MBytes 199 Mbits/sec
[ 3] 22.0-23.0 sec 23.5 MBytes 197 Mbits/sec
[ 3] 23.0-24.0 sec 22.8 MBytes 191 Mbits/sec
[ 3] 24.0-25.0 sec 23.1 MBytes 194 Mbits/sec
[ 3] 25.0-26.0 sec 23.4 MBytes 196 Mbits/sec
[ 3] 26.0-27.0 sec 23.1 MBytes 194 Mbits/sec
[ 3] 27.0-28.0 sec 23.6 MBytes 198 Mbits/sec
[ 3] 28.0-29.0 sec 23.5 MBytes 197 Mbits/sec
[ 3] 29.0-30.0 sec 22.9 MBytes 192 Mbits/sec
[ 3] 30.0-31.0 sec 23.8 MBytes 199 Mbits/sec
[ 3] 31.0-32.0 sec 24.0 MBytes 201 Mbits/sec
[ 3] 32.0-33.0 sec 23.5 MBytes 197 Mbits/sec
[ 3] 33.0-34.0 sec 23.0 MBytes 193 Mbits/sec
[ 3] 34.0-35.0 sec 23.6 MBytes 198 Mbits/sec
[ 3] 35.0-36.0 sec 23.2 MBytes 195 Mbits/sec
[ 3] 36.0-37.0 sec 23.9 MBytes 200 Mbits/sec
[ 3] 37.0-38.0 sec 23.6 MBytes 198 Mbits/sec
[ 3] 38.0-39.0 sec 23.2 MBytes 195 Mbits/sec
[ 3] 39.0-40.0 sec 23.8 MBytes 199 Mbits/sec
[ 3] 40.0-41.0 sec 24.0 MBytes 201 Mbits/sec
[ 3] 41.0-42.0 sec 23.4 MBytes 196 Mbits/sec
[ 3] 42.0-43.0 sec 23.8 MBytes 199 Mbits/sec
[ 3] 43.0-44.0 sec 23.0 MBytes 193 Mbits/sec
[ 3] 44.0-45.0 sec 23.5 MBytes 197 Mbits/sec
[ 3] 45.0-46.0 sec 22.6 MBytes 190 Mbits/sec
[ 3] 46.0-47.0 sec 12.5 MBytes 105 Mbits/sec
[ 3] 47.0-48.0 sec 11.9 MBytes 99.6 Mbits/sec
[ 3] 48.0-49.0 sec 12.5 MBytes 105 Mbits/sec
[ 3] 49.0-50.0 sec 15.2 MBytes 128 Mbits/sec
[ 3] 0.0-50.0 sec 1134 MBytes 190 Mbits/sec
Done.

[Scott Fella]

What I have done for perf testing in the past is to use udp. Here is my setup with 9130’s on flex:

MacBook Pro:
➜ ~ iperf3 -c 10.10.202.204 -f m -u -b 2g
Connecting to host 10.10.202.204, port 5201
[ 5] local 10.10.208.185 port 55142 connected to 10.10.202.204 port 5201
[ ID] Interval Transfer Bitrate Total Datagrams
[ 5] 0.00-1.00 sec 160 MBytes 1344 Mbits/sec 135702
[ 5] 1.00-2.00 sec 138 MBytes 1156 Mbits/sec 116734
[ 5] 2.00-3.00 sec 156 MBytes 1307 Mbits/sec 131956
[ 5] 3.00-4.00 sec 169 MBytes 1418 Mbits/sec 143183
[ 5] 4.00-5.00 sec 160 MBytes 1344 Mbits/sec 135723
[ 5] 5.00-6.00 sec 170 MBytes 1429 Mbits/sec 144340
[ 5] 6.00-7.00 sec 162 MBytes 1359 Mbits/sec 137220
[ 5] 7.00-8.00 sec 165 MBytes 1383 Mbits/sec 139610
[ 5] 8.00-9.00 sec 172 MBytes 1442 Mbits/sec 145605
[ 5] 9.00-10.00 sec 150 MBytes 1256 Mbits/sec 126782
- - - - - - - - - - - - - - - - - - - - - - - - -
[ ID] Interval Transfer Bitrate Jitter Lost/Total Datagrams
[ 5] 0.00-10.00 sec 1.56 GBytes 1344 Mbits/sec 0.000 ms 0/1356855 (0%) sender
[ 5] 0.00-10.11 sec 334 MBytes 277 Mbits/sec 0.029 ms 1074207/1356789 (79%) receiver


➜ ~ iperf3 -c 10.10.202.204 -f m -b 2g
Connecting to host 10.10.202.204, port 5201
[ 5] local 10.10.208.185 port 62660 connected to 10.10.202.204 port 5201
[ ID] Interval Transfer Bitrate
[ 5] 0.00-1.00 sec 11.7 MBytes 98.3 Mbits/sec
[ 5] 1.00-2.00 sec 28.4 MBytes 238 Mbits/sec
[ 5] 2.00-3.00 sec 26.4 MBytes 222 Mbits/sec
[ 5] 3.00-4.00 sec 28.2 MBytes 236 Mbits/sec
[ 5] 4.00-5.00 sec 28.9 MBytes 243 Mbits/sec
[ 5] 5.00-6.00 sec 26.4 MBytes 221 Mbits/sec
[ 5] 6.00-7.00 sec 28.1 MBytes 236 Mbits/sec
[ 5] 7.00-8.00 sec 28.2 MBytes 237 Mbits/sec
[ 5] 8.00-9.00 sec 27.9 MBytes 234 Mbits/sec
[ 5] 9.00-10.00 sec 24.5 MBytes 205 Mbits/sec
- - - - - - - - - - - - - - - - - - - - - - - - -
[ ID] Interval Transfer Bitrate
[ 5] 0.00-10.00 sec 259 MBytes 217 Mbits/sec sender
[ 5] 0.00-10.03 sec 258 MBytes 216 Mbits/sec receiver

[Evanjrosado]

Thanks Scott. I will try this. I just upgraded my Spectrum internet service to their 400meg internet speed. Attached are results from an 802.11ax and ac client. I'm getting the full throughput which is awesome. Its just that i'm expecting more between my client on my network. 

[Scott Fella]

I upgraded my internet also but my Meraki MX is my bottleneck. I don’t really care to be honest as I max out over the internet around 250Mbps. My Iperf test also depends on where I’m at and devices that I use to test.